Controlling algae with 5-(5 barbiturilidene)-rhodanine

ABSTRACT

The compound 5-(5&#39;&#39;-Barbiturilidene)-Rhodanine can be used to inhibit and/or prevent the growth of many undesirable forms of algae. This invention is particularly concerned with the algaecidal properties of 5-(5&#39;&#39;-barbiturilidene)-rhodanine against the algae species Scenedesmus, Plectonema, Anabaena, Ankistrodesmus, Oscillatoria, Coccochloris, Chlamydomonas, Lyngbya, Synura, and Chlorella.

United States Patent [191 [111 3,765,864 Kerst et al. Oct. 16, 1973CONTROLLING ALGAE WITH 5-(5 BARBITURILIDENE)-RHODANINE m y m n L i Gotts[75] Inventors: Al F. Kerst; John D. Douros, Jr., 3 g gg i i Mills bothof Littleton; Milan Brokl, "0mey .aymon m e a Denver, all of C010. [73]Assignee: The Gates Rubber Company, [.57] ABSTRACT Denver Colo Thecompound 5-(5-Barbiturilidene)-Rh0danine can be used to inhibit and/orprevent the growth of many [22] Fled: 1971 undesirable forms of algae.This invention is particu- [211 App! 175,341 larly concerned withthe-algaecidal properties of 5- (5'-barbiturilidene)-rhodanine againstthe algae species Scenedesmus, Plectonema, Anabaena, Ankistrode- [52]US. Cl 71/67, 71/90, 260/257 smus, o ill fi Coccochloris, chlamydomonasy[51] Int. Cl A0ln 9/12 Lyngbya, Synum, and Chlorel1a [58] Field ofSearch 71/67, 90; 424/254;

2 0 257 13 Claims, No Drawings CONTROLLING ALGAE WITH -(5BARBITURILIDENE)-RI-IODANINE BACKGROUND OF THE INVENTION 34,279 (1962)have reported the use of a wide variety of chemical algaecides such ascopper sulphates, chlorine, quaternary ammonium, rosin amines, quinones,activated silver, antibiotics and organic zinc compounds. Representativepatented algaecidal compounds can be found in US. Pat. Nos. 2,999,810;

3,052,594; 3,396,158 and 3,481,730. Furthermore 0 many microorganisminhibiting compounds contain the barbituric acid nucleus;

wherein R represents various substituents. Representative biologicallyactive barbituric compounds are found in U.S. Pat. Nos. 2,561,688;2,605,209; 2,725,380; 2,820,035, 2,887,487 and 3,102,072. The algaecidalproperties of 5-(5-barbiturilidene)-rhodanine how- 3 ever, have not beenpreviously discovered.

SUMMARY OF THE INVENTION According to the present invention, it has beenfound that 5-(5'-barbiturilidene)-rhodanine compounds are very effectivealgaecidal agents. The compound 5-(5'-bariturilidene)-rhodanine has beenknown to the chemical arts for many years. The 5-(5- barbiturilidene)-rhodanine used in this invention is prepared by a procedure whereby16.00 gr. (0.1 mole l of alloxan-monohydrate and 13.32 gt. (0.1 mole) ofrhodanine are condensed in 150 ml. of glacial acetic acid. The reactionis carried out in a reflux condenser for about 3 hours with continuousstirring. The temperature is controlled by a water bath and maintainedat 6070 C. After the reaction time, a yellow solution of the product isevaporated under vacuum to about onethird of the original volume anddiluted with the same amount of water, and allowed to stand in arefrigerator overnight. The product forms yellow crystals and isseparated on a sintered glass funnel and washed thoroughly with smallamounts of water. A small part of the compound is obtained from thefiltrate after evaporation at a diminished pressure and treatment withwater.

The crude product is purified by recrystallization from methanol withcarbon treatment yielding a product (13.2 g., 51.36 percentof'theoretical) which has a melting point of l72175 C.

UTILITY OF THE INVENTION The presence of algae in water can result insuch deleterious effects as rampant plant growth, health hazards,discoloration, bad taste and odor as well as blockage of pipes, filters,tanks and similar equipment. The applicants have discovered that5-(5'-barbiturilidene)- rhodanine compounds can be used to inhibit thegrowth of a wide variety of algae species which cause these problems inwater supplies. For example 5-(5'- barbiturilidene)-rhodanine compoundsmay be employed against: (1) taste and odor causing algae such asAnabaena and Synura; (2) filter clogging algae such as Chlorella,Oscillatoria, and Anabaena; (3) polluted water algae such as Lyngbya,Chlamydomonas, Anabaena and Oscillatoria, (4) clean water algae such asAnkistrodesmus and (5) surface water algae such as Scenedesmus.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The algaecidal effectiveness of5-( 5 barbiturilidene)rhodanine against these species is determined bythe following test. Algal cultures representing Scenedesmus, Chlorella,Plectonema, Anacystis, Ankistrodesmus, Anabaena, Synura, Oscillatoria,Chlamydomonas, Coccochloris and Lyngbya are each maintained in Chu No.10 Broth Medium (Calcium nitrate, 0.040 grams; Potassium phosphate,0.010 grams;

Magnesium sulphate, 0.025 grams; Sodium carbonate, 5 0.020 grams; Sodiumsilicate, 0.025 grams; Ferric citrate, 0.003 grams; Citric acid, 0.003grams and deionized water, 1,000 ml.) in the presence of sunlight.Hardened Chu No. 10 Agar plates are inoculated with cotton swabssaturated with the respective algae broth 0 cultures. The 5-(5'-barbiturilidene)-rhodanine is tested by impregnating filter paperdiscs (1.27 cm. in diameter, No. 740-E. Schleicher and Schuell, Keene,New Hampshire) with 0.08 ml. of a 5-(5'-barbituri1idene)- rhodaninesolution. The saturated filter discs are placed onthe surfact of theseeded agar plates and the optimum broth temperature of 25 to 27 C. ismaintained. Untreated controls are used as a basis of comparison andthese exhibit profuse algae growth. The results of these tests areexpressed as inhibition zone di- 0 ameters in centimeters.

Com ound:

. Zones of Inhibition for 5-(5'-barbiturilidene Various Concentrationsrhodanine Algae 10 3 ug/disc ugldisc ug/disc Scenedzsmus basilemis TaftI EEC 83 3.4 2.4 1.3 Scenedesmus nbliquus Taft EEC 92 2.2 1.5 trScenedesmus obliquus SR1 2.2 1.3 tr Chlorella vulgari: ATCC 9765 2.7 1.5tr Plectonema nolalum Taft EEC 172 1.8 1.1 tr Anacysti: m'dulans TaftEEC 134 1.4 tr tr Ankislrodesmus var. aciculari: Tafi EEC 28 1.8 1.0 trAnabaena catenula SR1 3.0 2.1 1.0 Synum ulvella UI 3.1 2.2 1.1Oscillalon'a corneri U1 3.4 2.5 1.3 Coccochlori: eleban: SR1 2.0 1.1 tr

Chlamydomonas radiali UA Lyngbya sp. Taft EEC 166 tr trace Those skilledin the art will recognize that the scope of this invention should not belimited to the particular species of the above genera. For instance,thenoted activity of -(5'-barbiturilidene)-rhodanine against Chlorellavulgaris suggests that the compound will also prove to be of valueagainst such other Chlorella species such as Chlorella ellipsoidea,Chlorella pyrenoidosa, chlorella variegate, etc. Similar possibilitiesexist for species of the other genera whose activity was shown to bearrested by 5-(5'-barbiturilidene)- rhodanine. It should also berecognized that other appropriate algae genera may well affordadditional opportunities to further define the degree and spectrum ofthe algaecidal activity disclosed in this invention. Since no firmprocedure can be laid down for the sequencing of such evaluations or fora selection among the more than 20,0007known algae species, the 5-(5'-barbiturilidene) rhodanine compoundsof this invention must be consideredon the basis of their demonstrated performance in these primaryevaluations and then progressively judged in subsequent studies.

Subsequent evaluations should include but not be limited to thefollowing algae genera.

Taste and Odor Causing Algae Genera Asterionella Peridinium NitellaAnabaena Mallomonas Dinobryon Microcystis Aphanizomenon VolvoxUroglenopsis Staurastrum Pandorina Hydrodictyon Ceratiurn Synura SynedraCcelosphaerium Clean Water Algae Genera Rhizoclonium MerismopediaMeridion Pinnularia Aphanothece Chromulina Cladophora Ulothrix PhacotusRhodomonas Navicula- Staurastrum Surirella Chamaesiphon LemaneaCyclctella Micrasterias Cocconeis Chrysococcus Calothrix MicrocoleusAnkistrodesmus Polluted Water Algae Genera Arthrospira TetraedronAnabaena Merismopedia Euglena Phacus Phonnidium Spircgyra GloeogapsaCarteria Chlorococcum Stigeocioniurn Lepocinclis Oscillatoria GomphonemaNitzschia Lyngbya Chlamydomonas Chlamydobotrys Filter Clogging AlgaeGenera Anabaena Closterium Spirogyra Chroococcus TabellariaTrachelomcnas Dinobryon Rivularia Asterionella Cymbella MelosiraPalmella Chlorella Cyclotella Diatoma Synedra Navicula FragilaraiTribonema Oscillatoria Surface Water Algae Genera Actinastrum EuastrumZygnema Nodularia Gonium Stauroneis Coeiastrum Desmidium SphaerocystisEuglena Pediastrurn Scenedesmus Micractinium Eudorina Oocystis MougeotiaGomphosphaeria Reservoir Algae Genera Chara. Audouinella CompsopogonPhormidium Tetraspora Batrachospermum Ulothrix Achnanthes CymbellaCladophora Stigeoclonium Bulbochaete Gomphonema Lyngbya Draparnaldia Itshould also be recognized that the use of algaecidal5-(5'-barbiturilidene)-rhodanine compounds should not be restricted to'any particular area of application. The scope of this invention shouldencompass the use of 5-(5'-barbiturilidene )-rhodanine in waters of alltypes such as lakes, rivers, streams, reservoirs, ponds, oceans, aswellas recirculating industrial waters. Furthermore,S-(S'-barbiturilidene)-rhodanine compounds of the present invention arealso advantageous in that they are biodegradable with none of thedegradation products being toxic to fish and most fish food organisma atalgae killing concentrations.

Another important advantage of 5-( S"- barbiturilidene)-rhodaninecompounds in their algaecidal applications is that they can be made upin solid or liquid formulations. Examples of solid formulations aredust, wettable powders, granules and pellets known to the crop dustingart. Solid formulations, particularly floating solid formulations, maybe preferred in combating algae which grow on surface waters. As a dust,5-(5'-barbiturilidene)-rhodanine compounds may be dispersed in powderedsolid carriers such as talc, soaps, soapstone, attapulgus clay as wellas other finely divided solids. When formulated as wettable powders, theactive 5-(5'-barbiturilidene)-rhodanine component may be employed inconjunction with inert fillers which may be of the clay type carrier ornon-clay type, in conjunction with various combinations of wettingagents and emulsifiers which may permit the adaptation of theconcentration as a free-flowing powder. Each of these carriers maycontain one or more of the specified 5(5 barbituriiidene)-rhodaninecompounds with other carriers which are ordinarily non-reacting or inertsubstances such as sand, clays, talc, sawdust, alkaline earthcarbonates, oxides, phosphates and the like as well as diatomaceousearth, micas or other suitable materials.

When liquid formulations are desired, liquid extenders dilutants orcarriers of non-reactive nature may be utilized. These compositionsshould contain approximately 0.1 to 20 percent by weight and preferably1 to 10 percent and most preferably 1 to 3 percent of the active 5-(5'-barbiturilidene)-rhodanine ingredient. Solvents which may be used inthe preparation of such compositions would include alcohols, ketones,glycols, mineral spirits and aromatic solvents such as benzene, xylene,nitrobenzene and dimethylformide. Furthermore, to assist in the rapidand complete dispersion inwater systems, these5-(5'-barbtiurilidene)-rhodanine compositions may also containapproximately 5 to 30 percent by weight and preferable 10 to 15 percentby weight of surface-active agents. Suitable surface-active agentsinclude sodiumdialkyl sulphates, sodium alkylbenzene sulfonates, sodiumcarboxylates and nonionic surfactants such as ethoxylated fatty acidalcohols and aminesf Where it is desired to use wettable powders orliquid formulations, 'either emulsified, dispersed, or suspended inwater or other. fluids, one or more of the class of materials hereinreferred to as adjuvants may also be incorporated into the powder, dustor liquid formulation. These adjuvants may comprise surface activeagents, detergents, wettable agents, stabilizers, dispersing agents,suspending agents, emulsifying agents, spreaders, stickers andconditioning agents generally. Through their modifying characteristicsthese adjuvants may facilitate handling application and may enhance orpotentiate the 5-(5-barbiturilidene)- rhodanine compounds of thisinvention in their algaecidal, bactericidal or fungicidal activities bymechanisms which are frequently not well understood. A satisfactory butnot exhaustive list of these adjuvants appears in Soap ChemicalSpecialties, Volume 31, No. 7, Page 61; No. 8, Pages 48 61; No. 9, Pages52 67 and No. 10, Pages 38 67 (1955). See also bulletin No. 607 of theBureau of Entomology and Plant Quarantine of the United StatesDepartment of Agriculture.

An additional advantage of the 5-(5'- barbiturilidene)-rhodaninecompositions of this invention is their compatability with a widevariety of other algaecidal, biocidal and fungicidal materials. Forexample, it may be convenient to combine one or more of the 5-(5-barbiturilidene)-rhodanine compositions with one or more of the otherbiocides, fungicies, or algaecides. For example, common fungicides andbiocides such as sulphur, inorganic salts such as copper sulphate,activated colloidal compounds, copper naphthenate and zinc acetate aswell as substituted hydrocarbons and quartemary ammonium compounds,amines and antibiotics may be employed in conjunction with5-(5'-barbiturilidene)-rhodanine compounds.

it should be recognized that other considerations may make some methodsof application more favored than others. These considerations mayinclude the type of organisms on which the compound is to beadministered, the degree of activity, the degree of inhibition towardthe algae organism and the possible environmental side effects. Also tobe considered is the cost of production and the characteristicsolubility of the com-v pounds into which the 5-(5'-barbiturilidenerhodanine may be introduced.

In their algaecidal aspects the Applicants have discovered that the 5-(5'-barbiturilidene)-rhodanine compounds of this invention are activealgaecides at relatively low concentrations. For example, it has beendiscovered that the 5-(5-barbiturilidene)-rhodanine have imparted a highdegree of algaecidal activity at concentrations as low as 0.1 ppm. Theamount of 5-(5'- barbiturilidene)-rhodanine added to the water will, ofcourse, vary depending upon such factors as the type of algae present,the nature of the body of water, i.e., flowing stream versus small lake,etc., and the inherent ability of the body of water to support algaegrowth. This inherent ability in turn depends upon such factors asexposure to sunlight, PH, nutrient capabilities and the like. In mostcases, however, the concentration of 5-(5-barbiturilidene)-rhodaninerequired to kill or inhibit growth of algaes will vary from 0.1 to 100ppm with the preferred range being to ppm.

The 5-(5-barbiturilidene)-rhodanine compounds of this invention can beadded to the water according to conventional techniques for algaecideapplication.

When treating a lake or body of water which is relatively calm, theconventional procedure is to spray an aqueous solution of the algaecideover the surface of the water. The 5-(5-barbiturilidene)-rhodaninegenerally will be predissolved in types of water soluble solventspreviously mentioned. In the case of moving water, such as in watertreatment plants or industrial facilities,5-(5'-barbiturilidene)-rhodanine algaecides can be added to the water insmall amounts at periodic intervals. For economic reasons, volume usagessuch as in lakes, streams and reservoirs as distinguished fromspecialized uses such as in aquatic gardens and industrial applications,the concentration of the 5-(5'- barbiturilidene)-rhodanine algaecidesprobably will not be over ppm.

Having thus disclosed our invention, we claim:

1. A method of killing, preventing or inhibiting the growth of algaewhich comprises applying an effective algaecidal amount of5-(5-barbiturilidene)-rhodanine to the algae.

2. The method of claim 1 wherein the algae are selected from the groupconsisting of Scenedesmus, Chlorella, Plectonema, Anacystis,Ankistrodesmus, Anabaena, Synura, Oscillatoria, Coccochloris,Chlamydomonas or Lyngbya.

3. The method of claim 2 wherein the Scenedesmus is selected from thegroup consisting of Scenedesmus basilensis or Scenedesmus obliquus.

A. The method of claim 2 wherein the Chlorella is Chlorella vulgaris.

5. The method of claim 2 wherein the Plactonema is Plectonema notatum.

6.T he method of claim 2 wherein the Ankistrodesmus is Ankistrodesmusacicularis.

7. The method of claim 2 wherein the Anabaena is Anabaena catenula.

8. The method of claim 2 wherein the Synura isbarbiturilidene)-rhodanine.

l *l i the

2. The method of claim 1 wherein the algae are selected from the groupconsisting of Scenedesmus, Chlorella, Plectonema, Anacystis,Ankistrodesmus, Anabaena, Synura, Oscillatoria, Coccochloris,Chlamydomonas or Lyngbya.
 3. The method of claim 2 wherein theScenedesmus is selected from the group consisting of Scenedesmusbasilensis or Scenedesmus obliquus.
 4. The method of claim 2 wherein theChlorella is Chlorella vulgaris.
 5. The method of claim 2 wherein thePlactonema is Plectonema notatum.
 6. The method of claim 2 wherein theAnkistrodesmus is Ankistrodesmus acicularis.
 7. The method of claim 2wherein the Anabaena is Anabaena catenula.
 8. The method of claim 2wherein the Synura is Synura ulvella.
 9. The method of claim 2 whereinthe Oscillatoria is Oscillatoria corneti.
 10. The method of claim 2wherein the Coccochloris is Coccochloris elebans.
 11. The method ofclaim 2 wherein the Chlamydomonas is Chlamydomonas radiati.
 12. Themethod of claim 2 wherein the Lyngbya is Lyngbya TAFT EEC
 166. 13. Themethod of killing algae selected from the group consisting ofScenedesmus, ChlorElla, Plectonema, Anacystis, Ankistrodesmus, Anabaena,Synura, Oscillatoria, Coccochloris, Chlamytomonas, Lyngbya, whichcomprises adding to water containing said algae from 0.1 to 100 partsper million of water of 5-(5''-barbiturilidene)-rhodanine.